I use separate emails for all accounts and that get's me in trouble when companies "consolidate" accounts because "everyone uses the same email for all accounts". Your good idea might be true, practice is not.
The parent was talking about different passwords, not different emails. But I'm curious, what does it mean for a company to consolidate accounts? How would that be done to your separate accounts automatically, and what trouble does it cause? And what is the normal case where people have multiple accounts all with the same email?
I just don't understand the circumstance you're describing.
I've had this twice now in one year ...